Note: submission will result in a HTTP 204 response to acknowledge;
in browsers this looks like a no-op

Publisher Diagnostics

Topic URL

Retrieve details about a topic URL.

These legal disclaimers are here because this hub is run by Google as
a service. If you don't want to agree to these terms you can use a
different hub or even run your own. The PubSubHubbub protocol is
decentralized and free.